The subject matter disclosed herein relates to the art of steam turbomachines and, more particularly, to a steam turbomachine valve having a valve member and seal assembly.
Steam turbomachine systems generally include multiple turbine sections each of which extracts work from a flow of steam. The multiple turbine sections may include a high pressure (HP) steam turbine portion, an intermediate pressure (IP) steam turbine portion, and a low pressure (LP) steam turbine portion. One or more valves control the flow of steam passing from one of the turbine sections to others of the turbine sections and, in some cases, to a heat recovery steam generator (HRSG). Each of the one or more valves includes a valve body that supports a valve member. The position of the valve member is selectively controlled to block passage of the steam flow or allow the steam flow to pass. The valve includes a seal between the valve member and the valve body. In most cases, the seal is provided on the valve member and is positioned to prevent the flow of steam from passing through a gap between the valve member and the valve body and to maintain a lower pressure upstream of the valve.